Field of the Invention
The present invention relates to wireless communications, and more particularly, to a method and apparatus for handling a secondary cell (SCell) deactivation timer in a wireless communication system.
Related Art
3rd generation partnership project (3GPP) long-term evolution (LTE) is a technology for enabling high-speed packet communications. Many schemes have been proposed for the LTE objective including those that aim to reduce user and provider costs, improve service quality, and expand and improve coverage and system capacity. The 3GPP LTE requires reduced cost per bit, increased service availability, flexible use of a frequency band, a simple structure, an open interface, and adequate power consumption of a terminal as an upper-level requirement.
The 3GPP LTE may provide a multimedia broadcast multicast service (MBMS) service. The MBMS is a service which simultaneously transmits data packets to multiple users. If a specific level of users exists in the same cell, the respective users can be allowed to share necessary resources so that the plurality of users can receive the same multimedia data, thereby increasing resource efficiency. In addition, a multimedia service can be used with a low cost from the perspective of users.
The 3GPP LTE may configure carrier aggregation (CA). In CA, two or more component carriers (CCs) are aggregated in order to support wider transmission bandwidths up to 100 MHz. A user equipment (UE) may simultaneously receive or transmit on one or multiple CCs depending on its capabilities. In CA, one primary cell (PCell) and at least one secondary cell (SCell) may be configured.
If the UE is configured with one or more SCells, the network may activate and deactivate the configured SCells. The PCell is always activated. For activation/deactivation of the SCell, a SCell deactivation timer may be used. For a specific channel/service, a method for handling the SCell deactivation timer efficiently may be required.